1. Field of the Invention
The present invention relates generally to mobile work platforms, sometimes referred to as moveable pedestal type scaffold units. More particularly this invention relates to an improvement which allows the loading of the apparatus onto an elevated surface.
2. Description of the Prior Art
Moveable work platforms generally have a base on wheels and an extensible mast portion mounted to the base and designed to extend upwards therefrom. These work platforms are typically difficult to move from one horizontal level to another, such as from the ground to a pick-up truck for transport. This is particularly true when only one or two persons are available to assist in the loading.
Prior methods for fascilitating loading are exemplified in the previously issued U.S. Pat. No. 4,592,447. In that reference a mobile work platform (moveable pedestal scaffold) is assisted in the function of laoding the mobile platform onto an elevated surface by the attachment of a frame structure to the side of the mobile platform. Wheels are mounted to the frame structure and positioned to carry the weight of the scaffold when it is positioned on its side. Unfortunately, when the scaffold is tilted upon its side for loading onto the elevated surface and the side mounted wheels contact the elevated surface, the apparatus is placed in an unstable and dangerous situation. While the wheels are useful to allow the rolling of the apparatus when it is on its side, this very same rolling tendency creates the dangerous movement and uncertainty when the apparatus is in the middle of the loading process.
A similar device is disclosed in the U.S. Pat. No. 4,620,712, where a side mounted wheel device is affixed to the side of a power table. This is claimed to make the power table portable in a pick-up truck. When the table is rolled to the rear gate of the truck, the table is tilted toward the truck until the side wheels contact the rear gate; whereupon the operator lifts until the full weight can be placed upon the side mounted wheels. Thereafter, the table is rolled on the bed of the truck by the combination of the side mounted rollers and a set of base mounted rollers. This system is substantially the same as the previously mentioned system (U.S. Pat. No. 4,592,447), and likewise creates the same dangerous instability in the middle of the loading process where the side mounted wheels cause the apparatus to roll when being lifted by the operator.